With the rapid development of the electronics industry, the problem of short internal battery life in devices such as smartphones, headsets and tablets has become increasingly prominent. As the power supply is an essential part of the power supply, mobile charging bank is widely used with the characteristics of portability and compact, and has a pivotal position. With the market scale of electronic products increasing year by year, mobile power battery products emerge in endlessly, but its type is single. The design ideas are as follows:
1. Power module
Two pieces of lithium alloy metal are cut into a rectangular shape, and the two pieces of lithium alloy metal plate are connected in series in the circuit. When the output current increases and is connected to the module's 5V input, switch to the output voltage 5V, fixed power supply 1.4A(at normal amplitude), according to the requirements of the installation of smart devices, it can be directly charged into the electronic device.
2. Intelligent module
Lithium alloy metal plate by converting mechanical energy into electrical energy, the voltage input in the circuit is stable at about 5V. In the lithium battery circuit, the PCF8591 chip is used to collect the voltage and display it through the display module. TP5410 chip circuit in the voltage is lower than the charging voltage, can cut off the charging circuit, to prevent battery damage. When powering electronic devices, the charging bank will also disconnect from the charging circuit to protect the circuit.
3. Voltage detection circuit module
The display module cannot display until the voltage current value detected by the charge and discharge terminal is digitized. The transmission function of SCM display is controlled by PCF8591 chip. The function of the chip in the circuit is to realize the detection of digital and analog conversion, and display the value of the current and voltage in the circuit. Once the digital signal is converted and input to the microcontroller, the input information will be analyzed and output to the display module. It is mainly used for the output voltage of the alloy module of lithium alloy, the charging voltage of the battery module and the discharge voltage of the third module when charging.
4. Battery protection circuit module
Overdischarge of the battery will lead to low voltage, and overcharging will also lead to overvoltage, affecting the service life of the battery, so it is necessary to develop a battery protection circuit to prevent overcharge and overdischarge of the battery. The chip is designed with THE DW01 chip, which has overcharge, overdischarge, short circuit and overcurrent protection functions.
This study through the mechanical energy into electrical energy, we can realize the function of charging, on the one hand provide electricity for electric equipment, satisfy people in out or need electricity demand, such as outdoor, and played an important role in the project, on the other hand can effectively use mechanical energy produced during the people movement, have the "recycling" of energy.